blocked_range.h Source File

00001 /*
00002     Copyright 2005-2009 Intel Corporation.  All Rights Reserved.
00003 
00004     The source code contained or described herein and all documents related
00005     to the source code ("Material") are owned by Intel Corporation or its
00006     suppliers or licensors.  Title to the Material remains with Intel
00007     Corporation or its suppliers and licensors.  The Material is protected
00008     by worldwide copyright laws and treaty provisions.  No part of the
00009     Material may be used, copied, reproduced, modified, published, uploaded,
00010     posted, transmitted, distributed, or disclosed in any way without
00011     Intel's prior express written permission.
00012 
00013     No license under any patent, copyright, trade secret or other
00014     intellectual property right is granted to or conferred upon you by
00015     disclosure or delivery of the Materials, either expressly, by
00016     implication, inducement, estoppel or otherwise.  Any license under such
00017     intellectual property rights must be express and approved by Intel in
00018     writing.
00019 */
00020 
00021 #ifndef __TBB_blocked_range_H
00022 #define __TBB_blocked_range_H
00023 
00024 #include "tbb_stddef.h"
00025 
00026 namespace tbb {
00027 
00037 
00038 
00039 template<typename Value>
00040 class blocked_range {
00041 public:
00043 
00045     typedef Value const_iterator;
00046 
00048     typedef std::size_t size_type;
00049 
00051 
00052     blocked_range() : my_begin(), my_end() {}
00053 
00055     blocked_range( Value begin_, Value end_, size_type grainsize_=1 ) : 
00056         my_end(end_), my_begin(begin_), my_grainsize(grainsize_) 
00057     {
00058         __TBB_ASSERT( my_grainsize>0, "grainsize must be positive" );
00059     }
00060 
00062     const_iterator begin() const {return my_begin;}
00063 
00065     const_iterator end() const {return my_end;}
00066 
00068 
00069     size_type size() const {
00070         __TBB_ASSERT( !(end()<begin()), "size() unspecified if end()<begin()" );
00071         return size_type(my_end-my_begin);
00072     }
00073 
00075     size_type grainsize() const {return my_grainsize;}
00076 
00077     //------------------------------------------------------------------------
00078     // Methods that implement Range concept
00079     //------------------------------------------------------------------------
00080 
00082     bool empty() const {return !(my_begin<my_end);}
00083 
00085 
00086     bool is_divisible() const {return my_grainsize<size();}
00087 
00089 
00091     blocked_range( blocked_range& r, split ) : 
00092         my_end(r.my_end),
00093         my_begin(do_split(r)),
00094         my_grainsize(r.my_grainsize)
00095     {}
00096 
00097 private:
00099     Value my_end;
00100     Value my_begin;
00101     size_type my_grainsize;
00102 
00104 
00105     static Value do_split( blocked_range& r ) {
00106         __TBB_ASSERT( r.is_divisible(), "cannot split blocked_range that is not divisible" );
00107         Value middle = r.my_begin + (r.my_end-r.my_begin)/2u;
00108         r.my_end = middle;
00109         return middle;
00110     }
00111 
00112     template<typename RowValue, typename ColValue>
00113     friend class blocked_range2d;
00114 
00115     template<typename RowValue, typename ColValue, typename PageValue>
00116     friend class blocked_range3d;
00117 };
00118 
00119 } // namespace tbb 
00120 
00121 #endif /* __TBB_blocked_range_H */